Zinc-titanium-manganese alloys



Patented Oct. 14, 1947 Edward .-Byle and Edmund A. Anderson, Palmerton, Pa.,,.assignors eto ,The -New Jersey 'ZincComnany, New York,N." Y.,,,a corporation -q'fiNew Jersey .rNoillrawing- Application' May .-1 7,11 414, :Serial No. '536-,016

10 J Claims.

This invention relates to zin'c'base alloys and more particularly to zinc base alloys containing titanium, and aims to provide an improved zinc base alloycontaining titanium and manganese. By zinc basealloy is meant an alloy containing at least about 97% zinc.

The zinc base alloys of the invention contain from 0.01 to 1.6%, and preferably from 0.05.to titanium and are characterized by additionally containing from 0.05 to 1.5%, and preferably from 0.1 to 1%, .of manganese. The balanceof the alloy is substantially all zinc. Alloys of the invention may advantageously contain about,0.1% titanium, 0.3 to.0.6% .manganese, and the balancezinc. .Thelincbase of the alloys is preferably high grade zinc. Alloys of superior creep resistance, that is resistance to prolonged static loads well below theultimateylimit,v and of fine grain size when cast result'from the use, as the zinc base, of metal of high purity, such as zinc at least 99.99% pure. On the other hand, satisfactory alloysv are obtained With ,zincof the grade commonly used in the production of commercial rolled zinc, forexample zinc'metal containing 01-10% lead, 0.012% ironand 0.005%cadmium. The presence of 0.1% lead is suflicient, however, to impart to the alloys (as cast) acoarse, columnar grain structure similar to that of ordinary cast, zinc. If the alloy is rolled or :otherwise mechanically worked, the coarse graingstructure of the cast alloy disappears, andthe micro-structure and properties of 'the rolled or worked alloy ,are substantially independent ,of the ,grade -or purity of the zinc base within the limits hereinbefore mentioned.

The alloys of the invention are particularly adapted for rolling. -When transformed to .sheet or strip by suitable rolling procedure, 1thezalloys possess highJcreepresistance. The alloys may be hetmolled .at metaltemperatures of from 150 to 300 C.,'temperatures of from 200 to 240 C. giving very satisfactorymesults. .Thehot rolling may be a finishing operation consisting of say three or more passes through the .rolls, and. may be applied to metal either hot or cold rolled prior to the hot finishing. Cold rollingtends to decrease the creep resistance, but thegcharacteristic high -.creep resistance can be substantially restoredgby subsequent heat treatmentfsuch, for example, as

annealingfor a short period eta-temperature of ,.from 150 ,to 400 0., annealingin oil ,forabout five minutes at a temperature of about 275 C. giving very-satisfactory results. Cold rolling, at

least in the final .st,ages,.imp=arts to: the alloycer- 1taingadvantages,especiallywith respect' to tensile elongation. Alloys of the invention are 'to be considered cold rolled when the rolling (or other mechanical working) is carried out under thermal conditions resulting in a temperature of the rolled '5 strip orisheet after the final rolling pass (final coiltemperature) duesimply to the mechanical working, and: are to be considered hot rolled when the rollingis carried out under thermal conditions resulting in a final coil temperature of from 150 to'300 C.., and preferably from 200 to 240 C.

In the productionof the alloysof the invention, itis'preferable-to prepare an intermediate zincbase alloy containing a relatively high proportion of titanium. Conveniently, the inter- 115 mediate-alloy may contain about 4%-.of titanium,

and is prepared by heating a mixture of 96 parts of zinc and 4 parts of titaniumin a clay-carbo- ,rundum crucible at a temperature of 800 C. for about'8 hours. The intermediate alloy is cast into a thinslab and crushed to a convenient size for alloying. The final titanium content of the castintermediate valloy usually does not depart far from the contemplated 4%."Manganese is preferably introduced into the alloy'by preparing an intermediate zinc alloy of high manganese content. The intermediate alloys, in calculated amounts to give the desired titanium and manganese contents, are mixed With zinc metal and melted together and heldiata temperature of abouti500 C. foran hour or so. Very little titanium or.manganese islost in this heating.

The alloys of the invention.arecharacterizeid by .high creep resistance, dynamic ductility, tensile strength, tensile elongation and good bending properties. These characteristics, among; others, Lof ;.the alloys arexshovvn inthe following table. In the: table, fHQisscleroscope hardness; .D. D. :isbynamic ductility ,andis measured as the maxi- -mumildepth; in inchesoi amp that canbe formed by a standard plunger in an uncut sheet of the :metahwithout fracture; Tern. is; percent temper, sand ;is -;determined .;b.y the ,degree :to :which ;a c-ista-ndardjtest :stripreturns .tOzitS original posizlfion :after being Wrapped around a mandrel; T. S. is tensile strength (with the grain) in :nounclsper: square inch T. is tensile elongaon (withgthegrainl, incpercentjn arZinchtest :striixraand5,0.1R1 isthecreep rateor creep resistance (:Withithegrain) expressed as the .inil/terse zcreeprrrate a tthe .more creep resistant alloy .havingatherhigher. inverse creep. rate) which is the number ofzunitspf time (days) ;-required to produce an elongation .or creep '(With'-the..grain) of 19116 pereentfli. ie. ,days:per%) ina standard test -piece:when subjected to-dead loads'of 8,000-and 12,000 pounds (respectively) per square inch at constant room temperature (25 C.). The cold bend values represent the diameter of uncracked 180 bends in multiples of sheet thickness (gauge), and the lower values indicate better bending properties. Cut and draw is the result of an actual drawing operation carried out on a disc cut from the sheet, and the figures given represent the percent decrease in diameter of the cup, as compared with the blank (per cent take-in) The columns headed by the single asterisk and by the double asterisk are results obtained with test pieces as rolled and as annealed for five minutes at 275 C. in oil, respectively. The titanium (Ti) and manganese (Mn) contents of the alloys given in the table are the amounts of these alloying metals added to the zinc base which was high purity metal. The alloys wer compounded in the manner here- 4 from 0.01 to 1.6% titanium and from 0.05 to 1.5% manganese and the balance essentially all zinc.

6. A hot rolled zinc base alloy containing at least about 97% zinc and characterized by high creep resistance and containing from 0.01 to 1.6% titanium and from 0.05 to 1.5% manganese and the balance essentially all zinc.

7. A cold rolled and annealed zinc base alloy containing at least about 97% zinc and characterized by high creep resistance and containing from 0.05 to 0.5% titanium and from 0.1 to 1% manganese and the balance essentially all zinc.

8. A zinc base alloy according to claim 7 containing about 0.1% titanium and from 0.3 to 0.6% manganese.

9. A hot rolled zinc base alloy containing at least about 97 zinc and characterized by high creep resistance and containing from 0.05 to 0.5%

inbefore described. titanium and from 0.1 to 1 manganese and the Table Cold Bends Creep Resistance Test out Ti Mn Grange H D. D. Tem. W h A '1. S '1. E and i 3,000 1). s. i. 12,000 p. s. i. draw I #I 1! II *3 8 2* k 1* *fl *4 1 05 0145 22 20 .290 .300 47 43 3 2 2 2 22, 800 22, 500 33. 7 23. 8 1. 53 434. 8 .040 33. 8 -40. 8 1 .10 0185 23 20 305 .305 46 42 3 3 2 2 23, 000 23. 100. 39. 5 30.3 1. 39 400. O .045 79. 4 41.2 .1 20 .018 24 20 .3l5 305 45 44 3 3 2 2 24, 900 22,900 41. 0 35. 8 1.61 555. 6 .006 131.6 41. 4 1 3O 018 24 22 315 305 46 46 3 8 2 2 24, 400 24, 100 45. 2 33. 2 4. 40 476. 2 084 243. 9 42.1 1 .40 017 26 24 310 300 46 48 3 3 2 2 25,000 26, 700 39. 9 30. 5 4. 06 1. 000.0 .013 256. 4 41. 5

Rolling Treatment: Slab heated to 275 0., rough rolled to 0.09 in six passes; cold coil rolled on hot rolls to 0.018"1n four passes, final coil temperature about 160 C.

.1 05 .0155 16. 5 285 .310 47 5 4% 2 2 22, 500 19. 300 59. O 28. 5 .007 500.0 .0039 2. 11 40.8 l .10 0165 27 18 320 .300 46 42 5 2V 2 2 23, 000 20,700 66. 8 34. 3 12 384. 6 .007 22. 4 4C. 9 .1 .20 .0175 28 22 .320 .300 44 44 5 3 2 2 23,600 23, 500 75.2 27.2 .33 526.3 .011 232.0 40.9 .1 30 0175 29 25 330 295 44 48 5 3% 2 2 24, 100 25, 600 70. 2 33. 0 78 79. 2 018 500. 0 41. l .1 .40 .018 29.5 26 .330 .290 42 48 4% 4 2 2 23, 000 27,000 68.3 29.0 .70 526.3 .020 370.4 41.8

Rolling Treatment: Slab heated to 275 0., rough rolled to 0.09 in six passes; cold coil rolled on hot rolls to 0.036 in three passes; cold rolled to 0.018 In three passes Rolling Treatment: Flab heated to 2302C0 0.,zough rolled to 0.09 in ten passes; cold coil rolled on warm 1011s to 0.018" in five passes, final coil temperature 90l30 C.

Rolling Treatment: Slab heated to 230260 0., rough rolled to 0.09 in ten passes; cold coil rolled on hot rolls to 0.018 in three passes, final coil temperature HBO-185 0.

"As rolled.

We claim:

1. A zinc base alloy containing at least about 97 zinc and characterized by high creep resistance containing from 0.01 to 1.6% titanium and from 0.05 to 1.5% manganese and. the balance zinc.

2. A zinc base alloy containing at least about 97 zinc and characterized by high creep resistance containing from 0.05 to 0.5% titanium and from 0.1 to 1% manganese and the balance zinc.

3. A zinc base alloy containing at least about 97% zinc and characterized by high creep resistance containing about 0.1% titanium and from 0.3 to 0.6% manganese and the balance zinc.

4. A zinc base alloy containing at least about 97% zinc and characterized by high creep resistance containing about 0.1% titanium and about 0.5% manganese and the balance zinc.

5. A cold rolled and annealed zinc base alloy containing at least about 97% zinc and characterized by high creep resistance and containing "*As annealed.

balance essentially all zinc.

10. A zinc base alloy according to claim 9 containing about 0.1% titanium and from 0.3 to 0.6%

manganese.

EDWARD J. BOYLE. EDMUND A. ANDERSON.

REFERENCES CITED The following references are of record in the file of this patent:

OTHER REFERENCES Metals Handbook, 1939 edition, pages 1737, 1765, published by American Society for Metals, Cleveland, Ohio. 

